What is the purpose of the carbonator machine? I recall making sparkling water as a kid by mixing the right amount of sodium bicarbonate and tartaric acid (very similar to citric acid) and no hardware was needed: one just had to put them in water, shake until they went into solution and drink.
Just making sparkling water. You don't drink the water that reacts with the soda/acid though. The CO2 produced is pressure injected into a separate bottle.
